Earthly Branches (Di Zhi)

In one line: The Earthly Branches are 12 ancient "codes" — 2 more than the Heavenly Stems (Tian Gan) — used in old times to mark months and hours.

What is it?

There are 12 Earthly Branches in total:

Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, Hai

The least common multiple of 10 Stems × 12 Branches is 60, so the ancients used the "Sexagenary Cycle" (六十甲子) to mark years, months, days, and hours in rotation.

Why are they important?

Earthly Branches are more complex than Heavenly Stems — each branch hides Heavenly Stems inside (藏干), which is an important tool in BaZi analysis.

Branch	Element	Yin/Yang	Hidden Stems (Cang Gan)
Zi	Water	Yang	Gui
Chou	Earth	Yin	Ji, Gui, Xin
Yin	Wood	Yang	Jia, Bing, Wu
Mao	Wood	Yin	Yi
Chen	Earth	Yang	Wu, Yi, Gui
Si	Fire	Yin	Bing, Wu, Geng
Wu	Fire	Yang	Ding, Ji
Wei	Earth	Yin	Ji, Ding, Yi
Shen	Metal	Yang	Geng, Ren, Wu
You	Metal	Yin	Xin
Xu	Earth	Yang	Wu, Xin, Ding
Hai	Water	Yin	Ren, Jia

How to read it in your BaZi chart?

There are 4 main things to look at in the Earthly Branches:

Zodiac signs: Zi-Rat, Chou-Ox, Yin-Tiger, ... (the most familiar reading)
Months: Yin month (Lichun to Jingzhe), Mao month (Jingzhe to Qingming), ... (divided by solar terms)
Hours: Zi hour (23:00–01:00), Chou hour (01:00–03:00), ... (12 double-hours)
Interaction relations: branches have clashes, combinations, punishments, harms — far more complex than stems

Common Misconceptions

❌ "Branches are just zodiac signs" — the zodiac is only one popular expression of the branches. ❌ "12 branches correspond to 12 months" — they're actually divided by solar terms (节气), not calendar months. ❌ "Hidden stems can be ignored" — hidden stems are key to identifying patterns.

📜 Classical source: San Ming Tong Hui (《三命通会》) Vol. 1, "On Earthly Branches" 🔗 Next lesson: Five Elements (Wu Xing)